Among typical types of electric motor, there is a motor which includes a seal portion for sealing a gap between members configuring an outer frame of the motor. For example, Japanese Patent Application Publication No. 2014-039381 discloses an electric motor which includes a seal portion for sealing between an outer flange portion of a yoke and a peripheral edge portion of a bracket. With the seal portion, this electric motor may be configured to prevent water from infiltrating into the motor, such that the electric motor may be used outdoors, for example, on a vehicle, and the like.
In the electric motor as described above, the outer flange portion of the yoke contacts the peripheral edge portion of the bracket. Similarly, the seal portion in the motor is disposed on a radially inner side than the radial outer edge of said portion where the yoke contacts the bracket.
In this configuration, however, water may infiltrate between contact portions where the yoke and the bracket contact each other from the radial outer edge, such that the contact portions between the yoke and the bracket can be corroded. As a result, the waterproof property of the electric motor may be degraded due to the corrosion.
Further, the corrosion of the contact portions between the yoke and the bracket may spread radially inward, such that the corrosion may spread up to a portion positioned in the seal portion of the yoke and the bracket. In this case, the sealing condition provided by the seal portion between the yoke and the bracket may be insufficient and thus the waterproof property of the electric motor may be further degraded.